Digging tooth



Feb- 16, 1932 VAN coRTRlGHT MEKEEL 1,845,677

DIGGIANG TOOTH Filed March 9, 1929 Z'Sheets-Sheet 1 Fell 15 1932- VAN com-RIGHT MEKEEL 1,845,677

v DIGGING TOOTH Filed March 9,' 1929 2 Sheets-Sheet 2 laden/0m Patented F eb. 16, 1932 UNITED STATES PATENTI orF1cE DIGGING TOOTH Application filed March 9, 1929. Serial No.. 345,719.

This invention relates to improvements in a. digging tooth and more particularly to a reversible dipper tooth and consists ofl the matters hereinafter described and more part ticularly pointed out in the appended claims.

The dipper toothv as shown herein is of the digging or two-part, reversible type, consisting of a point and of abase; and the object of the invention is to produce a construction of the kind which will present a maximum of strength and of close lit ot the two parts of the assembly with a minimum of metal in the interlocking parts of the assembly, so that the greater part of the point, by weight, is usable before it is necessary to discard the old point for a new one.

Another object of the invention is to provide a construction of this type in which the two parts of the assembly will have a maximum ot contact.

The advantages of my invention will appear more fully as I proceed with my speci cation.

In the drawings- Figure 1 is a perspective view of my improved two-part reversible dipper tooth with part of the base casting cut away and shown in section to more clearly illustrate the connecting parts of the assembly.

Figure 2 is a perspective view of the nose end of the base casting.

Figure 3 is a transverse section through Figure 1 in a plane indicated by the line 3-3 of Figure 1.

Figure 4 is a view representing a section through Figure 1 in a plane indicated by the line 4-4 of Figure 1.

Figure 5 is a perspective view of the point.

Figure 6 is a perspective view of a wedgepin by means of which the two parts of the assembly are locked together.

A Figure 't' is a perspective view of a modihed Jform of the invention.

'i5 used in this embodiment of the invention.

Figure 8 is a perspective view of the point Figure 1l is a view representing a longitudinal central section through a modilied form of the point in the plane of the slot of the tenon.

Referring now to that embodiment of the invention illustrated in the drawings and particularly in Figures 1 to 6, inclusive 12 indicates the base and 13, the point, of my improved two-part, reversible dipper tooth. The point is of the usual wedge- 6U shaped section. The two parts, the base and the point, are connected together by a socket and tenon joint, which in the embodiment of the invention now being described, includes a tenon 14 extending rearwardly from the 65' base of the point 13, and a socket 15 cored or otherwise provided in the nose 16 of the base 12. The cross-section of the socket 15 may be of any suitable form, as desired; but preferably, and as shown, is square. vThe walls 17 of said socket flare or diverge outwardly toward the end of the nose of the base (see Figure 4) from a plane spaced rearwardly a short distance from said end. They likewise lare or diverge rearwardly from said plane to present a backdraft for the tenon 14 of the point, when expanded, as will be presently described.

The point 13 is formed to present a shoulder 18 at its'base to abut the end of the nose 80 16 of the base casting 12. The tenen of the point 14 is formed beyond the shoulder 18 to lit closely the outwardly flaring or diverging parts of the walls 17 of the recess 15 in the nose of the base. The main length of the '85 tenon is normally of such cross-sectiona1 area as -to engage loosely in the part of the recess 15 beyond the plane of the outwardly diverging walls thereof at the outer end of the recess.

The tenen 14 is provided with a slot or slots formed near the end with a tapered keyway or keyways to receive a correspondingly tapered pin or pins, adapted to expand the rear end part of the tenon. As shown, the tenon 14 has a single slot 19 extending :from a plane near the shoulder 18 on the point and open ing through the end of the tenen. 20 indi cates a tapered keyway. Said keyway is formed to receive a tapered pin 21, which is preferably of uniform radius in one plane, but of tapered, continuously reduced radius in a plane at right angles thereto. The nose of the base casting is provided with a hole or opening 22 extending through the nose with its axis substantially coinciding with the position to be occupied by the wedge-pin 21 when the tenon of the point is in its socket 15. i

To assemble the two parts of the construction, the tenon of the point 14 is inserted in the socket 15 of the nose and the shoulder 18 at the base of the point is brought against the end of the nose. The tapered pin 21 is then inserted through one end of the opening 22 in the nose and dro ped into the keyway 20, into which it is wedge-pin acts to expand the two parts of the tenon formed by reason of the slot 19, bringing them forcibly into engagement with the rearwardly flared parts of the walls 17 of the socket 15. A rigid connection between the two parts of the assembly is thus manifestly brought about. The tenon is engaged with the side walls of the recess throughout, and, because of the backdraft,- produced by reason of the rearwardly flaring parts of the walls 17 of the socket,a rigid lock against withdrawal of the tenon is brought about.

Disassembly of the two parts may be had by simpl drivingout the tapered wedge through t e opening 22 in the nose. The base and point are of forged steel, cast steel, or any other suitable metal, and I rely on the elasticity of such met-al to restore the rear end of the` tenon'to approximately its normal cross-section, when the wedge-pin is withdrawn. Should this not occur, however, the parts of the tenon may be forcedback to their original dimensions, by first tapping the point on one side and thenon the other when withdrawing the tenon from its socket.

It will be observed that the lock between the two parts of the assembly depends upon the engagement between the tenon of the point and the socket in the base. No strain, either tension or shear, is ever put upon the pin 21, which merely acts to expand the tenon, and therefore the only strain to which it is putis that of compression. Thus a relatively small pin may be used to produce a tight connection of the point and base with `a minimum chance of the point working loose from the base under the most severe service.

In Figures 7 to 10, inclusive, I have shown a somewhat modified form of the invention. In this case like p arts are indicated by like numerals with the letter a. In this case the parts are all of the same relative form and construction as in the rst case described. The tenon and its socket, however, are reversed in their application to the point and to the base. That is to say, whereas in the first case described the point was provided with the tenon and the base contained the orcibly driven. The

socket for the reception of the point, in the modified form the tenon is made a part of the base and the socket is formed in the point.

In this case 14a indicates the tenon formed on the nose 16a of the base 12a. 18a indicates a shoulder on the nose, which is adapted for engagement with the base of the point 138L when the parts are assembled. The hole or opening 22a for the removal or insertion of the wedge-pin 21 is in this oase in the point,

instead of in the nose, of the base casting.

In this modification of the invention I have likewise shown an additional feature which may be included in the assembly, whether of the form shown in Fi res 1 to 6 inclusive, or of the form shown in igures 7 to 10 inclusive. This consists of tongues formed in one member of the assembly, which proj ect beyond the plane of the base of the point and are engaged in a recess in the other member of the assembly. As illustrated, this consists of tongues 23, 23 formed on the sides of the nose 16a and engaging in suitable recesses 24, 2A, formed in the sides of the point at the base thereof. This construction adds rigidity to the connection of the parts.

The form of wedge-pin, illustrated and preferred, 'has the following advantages Atwo opposed sides of the nin, namely 21, 21,

are rounded at any cross-section throughout the length of the pin. These two sides converge from top to bottom of the pin and thus provide the wedge. The remaining two sides 21", 21, are fiat, in consequence of the form of the other two sides just described. In other words, the pin is in the form of a flat wedge, with the converging sides of the wedge rounded at the corners, with a uniform curvature throughout the length of the wedge-pin. The keyway 20 (20a) in the tenon 14 (14a) is similarly formed. As a result, as will be obvious from an examination of Figure 3, the

rounded sides of the wedge-pin will be en- -gaged in full contact with the seat in the tenon throu hout the full depth of said tenon.

In the em odiment of the invention shown in Figures 1 to 6 inclusive, I preferably form the point as shown in Figure 11. In this case, 25 indicatesthe point as a whole; 26, the tenon, 27 the slot therein, and 28 the'keyway for the wedge-pin near the end of the tenon.

I have found that (when made of cast metal) if the point is cored, a more homogeneous structure of metal is produced. Where the point is cast solid, the metal is apt to be spongy. I therefore prefer to core the point, as indicated at 29. If desired, and preferably, this core is .extended into the part of the tenon containing the slot 27, as indicated at 30. The structure of the metal of the point outside of and beyond the core Vis homogeneous throughout and much stronger. The point is thus not only of greater strength', but of reduced weight. For the purpose of coring, as described, thehole or opening 31 is extended from the outer into the cored space.

I claim as my invention- 1. A two-part, reversible dipper tooth, comprising a base and a point, one of said parts having a socket and the other having a tenon, said socket having walls fiared outwardly in opposite directions from a plane spaced back from the open end of the socket, said tenon being formed to closel enga e the outwardly-dared walls of the soc et ad]acent the open end thereof, and means for expanding said tenon to engage the walls of said socket at the rear end thereof.

2. A two-part, reversible dipper tooth,"

comprising a base and a point, one of said parts having a socket and the other havin a tenon, said socket having walls iiared outwardly in opposite directions from a plane spaced back from the open end of the socket, said tenon being formed to closel engage the outwardly-flared walls of the soc et ad]acent the open end thereof, said tenon being slotted and being provided with a keyway near its end, and a wedge-pin adapted for engagement in said keyway.

3. A two-part, reversible dipper tooth, comprising a base having a socket in the nose end thereof, a point provided with a tenon adapted to engage in said socket, said tenon being slotted and being provided with a keyway adjacent its end, said socket havin walls iared outwardly in both directions rom a plane spaced from the end of said base, and b a wedge-pin having rounded sides converging from top to bottom, adapted for enga ement in said keyway, ing provided with a hole, said socket, for the insertion of said wedgepm.

4. In a multi-part digging tooth, a part having a socket, a part having a slotted tenon adapted to engage in said socket, and means for expanding said tenon in said socket when e two parts are in assembled relation.

5. In a multi-point digging tooth, a part f having a socket, a part having a slotted tenon adapted to engage in said socket, and means vfor expanding said tenon in said socket to lock said parts together by reason of the expansion of said tenon alone.

6. In a multi-point digging tooth, apart having a socket, a part having a slotted tenon adapted to engage in said socket, and means for expanding said tenon in said socket, said means engaging the tenon only.

In a multi-point digging tooth, apart having a socket, a part provided with a tenon adapted to engage in said socket, said tenon being slotted and being provided with a key way near its end, and a wedge-pin adapted for engagement in said keyway.

8. In a multi-point digging tooth, a part having a socket, a part provided with a tenon adapted to engage in said socket, said tenon surface of the point g. other part being the nose of the base eopening through d being slotted and being provided with a keyway near its end, and a wedge-pin adapted for engagement in said keyway, said wedge-pin engaging said keyway only.

A two-part, reversible dipper tooth, comprising a base and a point, one of the two having a socket, said socket having walls which Hare outwardly toward its rear end, and the other having a tenon adapted to engage in said socket, said tenon being slotted and being provided with a ke way near its end, and a wedge-pin adapted for engagement in said keyway.

10. In a multioint digging tooth, a part provided with a s oulder and with a slotted tenon projecting beyond said shoulder, the provided with a socket to receive said tenon and being adapted to abut against said first named shoulder when the parts are drawn together, and means for expanding said tenon in said socket.

11. In a multi-point digging tooth, a part provided with a shoulder and with a slotted tenon projecting beyond said shoulder, the other part. being provided with a socket to receive said tenon and being adapted to abut against said first named shoulder when the parts are drawn together, said socket having walls which flare outwardl. beyond its rear end, and means for expanding said tenon in said socket.

12. In a multi-point diggin tooth, including a base and a point, said ase and point eing provided with interlocking tenon and socket members for holding them in `.assembled relation, means for expanding said tenon in said socket, and means for providing aditional engaging parts to interlock the point and the base in planes outside of and beyond the first named interlockin 4members.

13. In a multi-part digging tooth including a point and a part to which said point is connected, the point being provided with a slotted tenon and the part being provided with a socket to receive said tenon, and means or expanding said tenon in said socket, said point being cored and the core extending into the slot in said tenon.

In testimony whereof I claim the foregoin as my invention, I aix my signature this 5t 1 day of March, A. D. 1929.

VAN CORTRIGHT MEKEEL.

iis 

